1. Field of Invention
The invention relates to a canister base of a mask, which is mounted on the oral and nasal part of the mask with an air-intake pipe connected to the canister. The air-intake pipe may be rotated and thereby the direction of canister is adjusted to adapt to the ambient space.
2. Description of the Related Art
A mask generally includes three primary components: a mask body, a canister, and a canister base connected to the mask body and the canister. The canister base may further comprise a loudspeaker, a drinking pipe, and an air-intake pipe.
The loudspeaker serves as a communication tool for the wearer. Since the air in the mask is blocked therein by the mask, the wearer's voice is mostly isolated from propagation. Thus, a loudspeaker is needed to amplify the sound to make it audible.
The drinking pipe is provided to serve the needs of the wearer of the mask when the wearer has to wear the mask for a long period of time. The drinking pipe extends out from inside of the canister base. When in use, one end of said drinking pipe is put into the wearer's mouth while the other end is connected to a canteen. When unused, the drinking pipe may be fixed onto the canister base.
The air-intake pipe is used in combination with the canister. Contaminated or toxic air becomes clean and non-toxic after filtered by the filter contained in the canister and then flows into the canister base through the air-intake pipe.
The canister usually protrudes substantially from the mask and takes up substantial space. In a confined space, a protruding canister often causes interference and hinders the wearer's action of fleeing or lifesaving.
There are about two viable ways to avoid interference on the canister. One is to manufacture a smaller canister without reducing its filtering efficiency. The possibility to reduce the size of a canister can be expected if more efficient filtering material is developed and larger filtering area can be packed into the limited space in a filter. Another feasible way is make the canister adjustable in orientation to adapt to the confined space where the wearer is in. And thus, the canister may still be adapted to the space without changing its volume.